Syringe

ABSTRACT

This disclosure describes devices and methods used to inject or aspirate fluid into or from various regions of the human body, such as the anterior chamber of the eye. The disclosed devices and methods provide improvements over conventional devices and methods in that an operator can perform a procedure using the disclosed device without an assistant. The disclosed devices and methods allow one-handed injection or aspiration of fluid into or from body tissue, and provide means for controlling the volume of injected or aspirated fluid.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 to U.S.Provisional Application No. 62/475,048, filed Mar. 22, 2017, thedisclosure of which is herein incorporated by reference in its entirety.

TECHNICAL FIELD

The invention relates generally to an apparatus used in the field ofmedicine and more particularly to an apparatus used to aspirate orinject fluid from or into the body.

BACKGROUND

The eye is a fluid-filled, closed system with a one-way valve. Theanterior chamber is the fluid-filled space inside the eye between theiris and the cornea's innermost surface, the endothelium. A normalanterior chamber depth is approximately between 2.5 mm and 3.5 mm and itcontains approximately 0.25 mL of fluid called aqueous humor. Aqueoushumor is produced by the ciliary body and flows from the posteriorchamber to the anterior chamber. Once in the anterior chamber, theaqueous humor then travels through a fine trabecular meshwork at theanterior chamber angle (the one-way valve) and leaves via the Canal ofSchlemm.

Intraocular pressure often measures between 10 and 22 mmHg. Thispressure represents the balance between the production and outflow ofaqueous humor. In some cases, intraocular pressure becomes elevated andmay threaten visual loss. To treat such cases, fluid may be aspiratedfrom the anterior chamber to lower the volume of the intraocular fluid,and consequently, lower the intraocular pressure. Anterior chamberparacentesis is the clinical term for removal of fluid from the anteriorchamber of the eye, wherein intraocular pressure can reach dangerouslevels.

There are numerous causes for the intraocular pressure to rise requiringurgent paracentesis of the anterior chamber including, but not limitedto, closure of the anterior chamber angle and accumulation of blood orinflammatory cells in the anterior chamber. In addition, the treatmentof certain ophthalmologic pathologies requires intraocular injection ofmedication or certain gases. These injections may lead to acuteelevations in pressure that increase the risk of permanent vision lossand require an emergent paracentesis.

Lowering intraocular pressure below its normal level may also bedesirable in some disease states. For instance, central retinal arteryocclusion results from an atherosclerotic embolic event; acutelyreducing intraocular pressure to levels below normal with a paracentesiswill increase retinal perfusion in an attempt to propagate the embolusdistally and minimize the amount of visual loss.

There are numerous nonemergent indications for an ophthalmologist toperform an anterior chamber paracentesis. Diagnostically, an anteriorchamber paracentesis can be used for aqueous humor sampling for asuspected infection, inflammation, to diagnose certain intraocularcancers such as lymphoma, and for intraocular drug level monitoring.

The anterior chamber paracentesis is often performed in an officesetting. One conventional method for performing paracentesis includesthe use of a tuberculin syringe. The cornea is anesthetized and thepatient is positioned in the slit lamp. The plunger of a tuberculinsyringe is slightly withdrawn to break the bead on the syringe. The tipof the needle is positioned at the corneal limbus, the needle is gentlyinserted through the cornea and angled anteriorly to reduce the risk ofthe tip of the needle injuring the ciliary body, iris, or lens as itenters the anterior chamber. The plunger is slowly withdrawn and thedesired fluid aspirated from the anterior chamber. The needle is thenwithdrawn from the eye.

Unfortunately, anterior chamber paracentesis is associated with serious,albeit infrequent, complications; these include endophthalmitis, cornealabscess, and mechanical trauma to the ciliary body, iris and lens. As aresult, anterior chamber paracentesis is used with reluctance.

The conventional tuberculin needle and syringe are not designed forparacentesis and contain elements that increase procedural risk. Theseundesirable design elements include the needle length and flexibility,needle tip sharpness and bevel angle, syringe plunger mechanics, andbarrel length, diameter, grip and shape.

The anterior chamber measures approximately 13 mm in diameter and 3 mmin depth and contains delicate ocular structures such as the cornea,ciliary body, iris, and lens. Insertion of the conventional 8 mm-12.7 mmtuberculin needle into this relatively small compartment means that eventhe smallest unintended movements on the part of a surgeon's hand orpatient's eye or head exposes these intraocular structures to potentialtrauma, including resultant bleeding, infection, and vision loss. Inaddition to its undesirable length, the conventional needle stiffness,needle tip sharpness, and bevel angle are not optimized to penetrate theperipheral cornea. As a result, the force and angle required to accessthe anterior chamber is suboptimal, prolonging the procedure andincreasing the risk of uncontrolled insertion and patient movement.

A conventional tuberculin syringe contains a plunger that requireswithdrawal in order to initiate and propagate suction. It is technicallydifficult for a surgeon to draw back the plunger while holding thesyringe barrel steady with the needle inside the anterior chamber.Therefore, the surgeon may ask an assistant to withdraw the plungerwhile the surgeon attempts to hold the syringe and needle steady insidethe eye. This cumbersome tandem procedure reduces the surgeon's controlover needle depth and direction, increasing risk of intraocular trauma,and reduces the surgeon's control over withdrawal volume. Alternatively,the surgeon removes the plunger before the procedure, in which caseaqueous fluid spontaneously leaks into the empty barrel in anuncontrolled fashion, further compromising the precision with which thedesired volume of aqueous fluid is removed and creating a dangerousportal exposing the intraocular compartment to infectious externalcontamination.

The anterior chamber contains approximately 0.25 mL of aqueous fluid. Aconventional tuberculin syringe barrel holds 1 mL volume, withgradations marked for every 0.01 mL. Therefore, the precision with whicha surgeon can measure a desired volume of aqueous is limited to anapproximation. In addition, the barrel's smooth surface, round shape andthin diameter are suboptimal for the fine motor manipulation and handcontrol required to perform a paracentesis. As a result of the aboveundesirable syringe features, the conventional paracentesis proceduremay be unreliable, unpredictable, inconsistent and dangerous.

In contrast to a paracentesis, an intracameral injection is theinjection of fluid into the anterior chamber. This procedure may beindicated to increase intraocular pressure if the pressure is too low,to inject medications such as anti-infective agents, and for othermedical reasons. Similar to the paracentesis, surgeons use conventionalsyringes to perform intracameral injections, thereby exposing theintraocular tissues to an unnecessary risk of trauma.

The paracentesis and injection devices and methods of the presentdisclosure are advantageous for use in medicine and particularly in thefield of ophthalmology. That is, paracentesis and injection devicestaught herein enable a practitioner to withdraw or inject fluid from,and into a person or animal using one hand, with or without the visualguide of a slit lamp or other radiologic or ultrasound guiding devices.

SUMMARY

The embodiments of the present disclosure contain a needle designed toallow a practitioner to aspirate or inject without contactingsurrounding structures. The above characteristics of the devices taughtherein can be particularly advantageous when trying to withdraw orinject fluid in or around an organ with delicate surrounding structuresthat are vulnerable to inadvertent trauma, such as the human eye.

The embodiments of the present disclosure allow a practitioner toaspirate or inject a precise, controllable volume of fluid. This can beparticularly advantageous when withdrawing fluid from a closed chamberthat is vulnerable to internal pressure variations, or when injectingmedication with a narrow therapeutic index.

The embodiments of the present disclosure differ from conventionalinstruments in that, during use, the length of the needle is designed topenetrate the anterior chamber of the eye only far enough as to aspirateor inject a desired fluid and not to reach other intraocular structuressuch as the iris, ciliary body, or lens. Additionally, the stiffness,sharpness, and bevel angle of the needle of the presently discloseddevice are designed for penetrating the cornea.

Additionally, a differentiating feature of the syringe of the presentdisclosure is the ability to operate the device with only one hand. Asecond user, such as a nurse or assistant is not needed to manipulatethe syringe plunger, as is often required with the conventional devicesand methods. Further still, the syringe of the present disclosure doesnot require special visualization equipment to aspirate or inject aspecified amount of fluid.

The embodiments of the present disclosure provide the practitioner withflexibility in selecting a preferred insertion site to access theanterior chamber of the eye. With a conventional device in anophthalmology application, the needle must be inserted horizontallyalong the iris plane at the corneal limbus. In the devices taughtherein, the needle can be inserted horizontally along the iris plane atthe corneal limbus, and can also be inserted safely at any point betweenthe anterior edge of the surgical limbus and the visual axisperpendicular to the corneal curvature. This can be particularlyadvantageous by making the insertion less awkward or cumbersome, if thepatient's eye or head is not steady, or if the limbus is scarred orotherwise difficult to access.

The embodiments of the present disclosure allow a practitioner toperform the paracentesis with enhanced sterility over other methods ofparacentesis, since it is a closed system. In existing paracentesismethods, a surgeon will remove the plunger before the procedure,creating a dangerous portal exposing the intraocular compartment tooutside infectious contamination.

It will be obvious to anyone practicing medicine outside the field ofophthalmology that the devices taught herein can be used, or modified towithdraw, collect or inject fluid from or into other parts of the body.For instance, lumbar puncture (spinal tap) is performed in the lowerback, in the lumbar region. During lumbar puncture, a needle is insertedbetween two lumbar bones (vertebrae) to remove a sample of cerebrospinalfluid—the fluid that surrounds the brain and spinal cord to protect themfrom injury.

A lumbar puncture can help diagnose serious infections, such asmeningitis; other disorders of the central nervous system, such asGuillain-Barre syndrome and multiple sclerosis, or cancers of the brainor spinal cord. Sometimes doctors use lumbar puncture to injectanesthetic medications or chemotherapy drugs into the cerebrospinalfluid. Other times it is used to measure or relieve the cerebrospinalfluid pressure.

Injections performed in areas other than the eye may require precisemanual control in order to access a particular tissue. For instance,intradermal injections are used for sensitivity tests, such astuberculosis, allergy, and local anesthesia tests, as well as forvaccinations. Conventional syringes require multiple hand maneuvers thatcan lead to increased risk of injecting fluid into an undesirablelocation, such as the subcutaneous, or muscle layer, beneath the skin.

In some embodiments of the present disclosure, an aspiration and/orinjection device for use in the field of medicine, and more specificallyfor use in ophthalmology to aspirate or inject fluids from or into theanterior chamber, is provided. The device advantageously provides asafe, simple, inexpensive aspirating or injecting syringe and includes abarrel (for collection of aspirated fluids, or for injection) a plungerand plunger seal, a needle to access the anterior chamber, and a handlewhich when squeezed directs the plunger rearwardly away from theinjection site to aspirate the fluid into the barrel or toward theinjection site to inject from the barrel.

In some embodiments, a syringe is provided comprising a syringe barrelhaving a first end couplable to a needle and an open second end.Additionally, the syringe of the present invention comprises a plungerseal disposed inside the syringe barrel and a plunger rod in the syringebarrel extending along a longitudinal axis between a first end coupledto the plunger seal and a second end opposite of the first end. Thesyringe further comprises a compressible handle coupled between aportion of the syringe barrel and the second end of the plunger rod,wherein compressing the compressible handle causes the syringe plungerto move rearwardly in the syringe barrel away from the needle.

In some embodiments of the present disclosure, a syringe is provided,comprising a syringe barrel having a first end couplable to a needle andan open second end and a plunger seal disposed inside the syringebarrel. The syringe further comprises a plunger rod disposed in thesyringe barrel extending along a longitudinal axis between a first endcoupled to the plunger seal and a second end opposite of the first end.The syringe comprises a compressible handle coupled between a portion ofthe syringe barrel and the second end of the plunger rod, whereincompressing the compressible handle causes the syringe plunger to moveforwardly in the syringe barrel toward the needle.

In some embodiments of the present disclosure, a method for aspirating afluid is provided comprising inserting a needle of a syringe device intoa chamber such that the needle is in fluid communication with both aninterior of the chamber and a syringe barrel of the syringe. The syringecomprises a plunger seal disposed inside the syringe barrel, and aplunger rod disposed in the syringe barrel extending along alongitudinal axis between a first end coupled to the plunger seal and asecond end opposite of the first end. The syringe further comprises acompressible handle coupled between a portion of the syringe barrel andthe second end of the plunger rod. The method for aspirating a fluidalso comprises compressing the compressible handle to move the plungerrod and the plunger seal rearwardly within the syringe barrel away fromthe needle to draw fluid from the chamber into the syringe barrel.

In some embodiments, a method for injecting a fluid is providedcomprising inserting a needle of a syringe device into an injectionsite. The syringe includes a plunger seal disposed inside a syringebarrel, and a plunger rod disposed in the syringe barrel extending alonga longitudinal axis between a first end coupled to the plunger seal anda second end opposite of the first end. The syringe further comprises acompressible handle coupled between a portion of the syringe barrel andthe second end of the plunger rod. The method for injecting a fluidfurther comprises compressing the compressible handle to move theplunger rod and the plunger seal forwardly within the syringe barreltoward the needle to inject a fluid from the syringe barrel into theinjection site.

Still other objects and advantages of the invention will in part beobvious and will in part be apparent from the specification anddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying figures illustrate one or more embodiments of theinvention. The drawings are not necessarily to scale. The presentinvention is illustrated by way of example, and not limitation, in theaccompanying figures wherein:

FIG. 1A illustrates a cross-sectional view of a syringe, according tovarious embodiments of the present disclosure.

FIG. 1B illustrates a cross-sectional view of the syringe from FIG. 1A,showing the syringe after the syringe handles have been squeezed toretract the plunger.

FIG. 2A illustrates a plan view of an embodiment of a syringe includinga stopper, according to various embodiments of the present disclosure.

FIG. 2B illustrates a cross-sectional view of the syringe of FIG. 2Afrom a horizontal plane extending through a stopper, according tovarious embodiments of the present disclosure.

FIG. 3 illustrates a plan view of another embodiment of a syringe,according to various embodiments of the present disclosure.

FIG. 4 illustrates a plan view of another embodiment of a syringe havingvarying arm lengths, according to various embodiments of the presentdisclosure.

FIG. 5 illustrates an anterior-posterior cross section through theanterior chamber of an exemplary human eye.

FIG. 6 illustrates an exemplary method describing the anterior chamberparacentesis or intracameral injection procedure using the devicestaught herein.

FIGS. 7A-7F illustrate a plan view of other embodiments of a syringewith varying handle and plunger lengths, according to variousembodiments of the present disclosure.

FIG. 8A illustrates a device including a syringe holder system,according to various embodiments of the present disclosure.

FIG. 8B illustrates another a device including a syringe holder system,according to various embodiments of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thedisclosed devices and methods, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.

In this application, the use of the singular includes the plural unlessspecifically stated otherwise. In this application, the use of “or”means “and/or” unless stated otherwise. Furthermore, the use of the term“including”, as well as other forms, such as “includes” and “included”,is not limiting. Any range described herein will be understood toinclude the endpoints and all values between the endpoints. “Multiple”will be understood to refer to two or more.

The section headings used herein are for organizational purposes onlyand are not to be construed as limiting the subject matter described.All documents, or portions of documents, cited in this application,including but not limited to patents, patent applications, articles,books, and treatises, are hereby expressly incorporated by reference intheir entirety for any purpose.

Referring first to FIG. 1A, a cross-sectional view of a syringe 100 inaccordance with an embodiment of the present disclosure is illustrated.As is depicted, the syringe 100 includes a needle 11 attached to abarrel 14, and a plunger 13 and a plunger seal 12 disposed, at least inpart, within the barrel 14. The handle 15 is attached to, or near, theplunger 13 at, or near, terminal endpoints 15A, 15B, and to, or near,the barrel 14 at, or near, terminal endpoints 15D, 15C.

In various embodiments, the handle 15 is provided in two or morecomponents disposed on different regions of the outer surface of thebarrel 14 and the plunger 13. In some embodiments, the components of thehandle 15 are disposed in diametrical opposition about the barrel 14 andthe plunger 13. The handle 15 may be configured to manipulate theplunger 13, while remaining sufficiently flexible to be compressed inthe direction of the arrows 19. The handle 15 may be provided in avariety of materials, including, but not limited to, various metals,composite materials, and plastics, such as polyethylene, polypropylene,or polyvinyl chloride.

The handle 15 can connect to the plunger 13 and the barrel 14 in avariety of ways. For example, the terminal endpoints 15A, 15B, 15D, 15Cmay comprise connectors that facilitate compression of the handle 15.For example, the terminal endpoints 15A, 15B, 15D, 15C may compriseliving hinges, pin joints, spring hinges, or the like. Alternatively,the handle 15 can be connected to the plunger 13 and the barrel 14 usinga variety of chemical means, including various adhesives, epoxies,welding, or the like. Additionally, in various embodiments, the handle15, the plunger 13, and the barrel 14 may comprise a single,injection-molded component.

In various embodiments, the handle 15 includes grips 16, 18 whichprovide a resting surface for the fingers of the operator of the syringe100. In some embodiments, the grips 16, 18 are diametrically disposedabout the barrel 14, and are provided in a variety of shapes and sizes.For example, the grips 16, 18 may be provided as concave, semi-circularrecesses in the outer surface of the handle 15. In other embodiments,for example, the grips 16, 18 can be provided in similar sizes andshapes, or can be provided in differing sizes and shapes to accommodatevarious possible geometries of an operator's fingers. Additionally, forexample, the grips 16, 18 can include ergonomic contours or siliconepads to reduce pressure points and improve comfort of the syringe 100during use.

In some embodiments, the syringe 100 includes a grip 17 disposed on, orproximate to the plunger 13. The grip 17 provides another restingsurface of at least one finger of an operator, and enables enhancedmanipulation of the device. For example, an operator may place an indexfinger on the grip 17, a thumb on the grip 18, and a middle finger onthe grip 16. An operator may rest their remaining fingers on variousother components or surfaces of the device, including on the handle 15or the barrel 14.

The syringe 100 comprises a needle 11 with a gauge, stiffness, bevel andlength to facilitate penetration of the outer layer of the eye, namelythe cornea, just slightly entering the anterior chamber, minimizing therisk of contacting other intraocular structures. In various embodiments,the length of needle 11 is configured to slightly enter the anteriorchamber during use of the syringe 100. The length of the needle 11 canbe about, more than, or less than 0.25, 0.50, 0.75, 1.0, 1.25, 1.50,1.75, 2.0, 2.25, 2.50, 2.75, 3.0, 3.25, 3.50, 3.75, 4.0, 4.25, 4.50,4.75 or 5.0 mm. These values can be used to define discrete lengths,such as 0.75 or 3.0 mm. These values can also be used to define a rangeof lengths, such as from about 0.50 to about 1.0 mm, or from about 2.75to about 3.0 mm.

Additionally, in various embodiments, the gauge of the needle 11 may beconfigured to facilitate penetration of the outer layer of the eye,namely the cornea. The gauge of the needle 11 can be about, more than,or less than 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,or 34 g. These values can be used to define discrete gauges, such as 25g or 27 g. These values can also be used to define a range of gauges,such as from about 26 to 28 g, or from about 25 to 32 g.

Additionally, in various embodiments, the needle 11 may be coated withvarious materials, such as silicone, to facilitate penetration throughthe cornea, or hydrophilic coatings to reduce friction between biologictissues and the needle 11. Further, the needle 11 may include varioustip configurations to facilitate penetration of bodily tissue, such asocular tissue. For example, in various embodiments, the needle 11 maycomprise a beveled tip, provided in a variety of bevel angles.

In some embodiments, during use of the syringe 100, pressure is placedon the grip 17, and the grips 16, 18 are grasped to stabilize the devicewhile the operator advances the needle 11 into the anterior chamber ofthe eye. Once the needle 11 has penetrated the outer layer of the eye(i.e. the cornea), and its tip is within the anterior chamber, pressureis applied on the grips 16 and 18 in the direction of the arrows 19(i.e. the handle 15 is compressed). As a result, since the plunger 13and the plunger seal 12 are attached to one another and can move freelywithin the barrel 14, the action of moving the grips 16, 18 in thedirection of the arrows 19 causes the handle 15 to straighten,withdrawing the plunger 13 and the plunger seal 12 rearwardly, away fromthe needle 11. In turn, the plunger 13 extends further out of the barrel14, and the plunger seal 12 moves closer to the open end of the barrel14, generating negative pressure in the barrel 14 to draw out fluid fromthe anterior chamber of the eye into the barrel 14.

FIG. 1B illustrates a cross-sectional view of the syringe 100 from FIG.1A, showing the syringe 100 after the handles 15 have been compressed byapplying pressure to the grips 16, 18 in the direction of the arrows 19.This motion causes the handle 15 to straighten, moving the grips 16, 18closer to each other (i.e. compressing the handle 15), and withdrawingthe plunger 13 and the plunger seal 12 rearwardly away from the needle11. In turn, the plunger 13 extends further out of the barrel 14, andthe plunger seal 12 moves closer to the open end of the barrel 14,generating negative pressure in the barrel 14 to draw fluid into thebarrel 14.

In various embodiments, the syringe 100 can be configured such that themaximum distance that the grips 16 and 18 can travel corresponds to acertain volume of withdrawn fluid. In some embodiments, the grips 16, 18are prevented from compressing further by contact with the outer surfaceof the barrel 14. In other embodiments, some other mechanical limitercan limit the movement of the grips 16, 18, such as a physical stop orsome upper threshold of device design and/or flexibility of the materialof the handle 15. This safe stop feature of the syringe 100 allows anoperator to use the syringe 100 without an assistant or directvisualization of the withdrawn liquid.

In some embodiments, the maximum volume of withdrawn fluid is adjustedby changing the angle of the handle 15 relative to the barrel 14. Forexample, increasing the angle of the handle 15 relative to the barrel 14increases the distance between the grips 16, 18, which allows theplunger 13 to be retracted further within the barrel 14, therebyincreasing the volume of fluid able to be withdrawn using the syringe100. Conversely, a smaller angle of the handle 15 relative to the barrel14 results in a shorter distance between the grips 16, 18, limiting thedistance the plunger 13 can be retracted within the barrel 14, therebydecreasing the volume of fluid able to be withdrawn using the syringe100.

FIG. 2A illustrates a plan view of an embodiment of a syringe 200including a stopper 20, according to various embodiments of the presentdisclosure. As is depicted, the syringe 200 includes a needle 21attached to a barrel 24, and a plunger 23 and a plunger seal 22disposed, at least in part, within the barrel 24. The handle 25 isattached to, or near, the plunger 23 at, or near, a first end, and to,or near, the barrel 24 at, or near, a second end.

In various embodiments, the handle 25 is provided in two or morecomponents disposed on different regions of the outer surface of thebarrel 24 and the plunger 23. In some embodiments, the components ofhandle 25 are disposed in diametrical opposition about the barrel 24 andthe plunger 23. The handle 25 may be configured to manipulate theplunger 23, while remaining sufficiently flexible to be compressed inthe direction of the arrows 29. The handle 25 may be provided in avariety of materials, including, but not limited to, various metals,composite materials, and plastics, such as polyethylene, polypropylene,or polyvinyl chloride.

The handle 25 can connect to the plunger 23 and the barrel 24 in avariety of ways. For example, the handle 25 may comprise connectors thatfacilitate compression of the handle 15. For example, the handle 25 maybe connected to the plunger 23 and the barrel 24 with living hinges, pinjoints, spring hinges, or the like. Alternatively, the handle 25 can beconnected to the plunger 23 and the barrel 24 using a variety ofchemical means, including various adhesives, epoxies, welding, or thelike. Additionally, in various embodiments, the handle 25, the plunger23, and the barrel 24 may be provided as a single, injection-moldedcomponent.

In various embodiments, the handle 25 includes grips 26, 28 whichprovide a resting surface for the fingers of the operator of the syringe200. In some embodiments, the grips 26, 28 are diametrically disposedabout the barrel 24, and are provided in a variety of shapes and sizes.For example, the grips 26, 28 may be provided as concave, semi-circularrecesses in the outer surface of the handle 25. In other embodiments,for example, the grips 26, 28 can be the provided in similar sizes andshapes, or can be provided in differing sizes and shapes to accommodatevarious possible geometries of an operator's fingers. Additionally, forexample, the grips 26, 28 can include ergonomic contours or siliconepads to reduce pressure points and improve comfort of the syringe 200during use.

In some embodiments, the syringe 200 includes a grip 27 disposed on, orproximate to the plunger 23. The grip 27 provides another restingsurface of at least one finger of an operator, and enables enhancedmanipulation of the device. For example, an operator may place an indexfinger on the grip 27, a thumb on the grip 28, and a middle finger onthe grip 26. An operator may rest their remaining fingers on variousother components or surfaces of the device, including on the handle 25or the barrel 24.

In various embodiments, the syringe 200 comprises a needle 21 with agauge, stiffness, bevel, and length to facilitate penetration of bodilytissue, such as the outer layer of the eye, namely the cornea, justslightly entering the anterior chamber, minimizing the risk ofcontacting other intraocular structures.

In some embodiments, the maximum volume of withdrawn fluid is adjustedby changing the angle of the handle 25 relative to the barrel 24. Forexample, increasing the angle of the handle 25 relative to the barrel 24increases the distance between the grips 26, 28, which allows theplunger 23 to be retracted further within the barrel 24, therebyincreasing the volume of fluid able to be withdrawn using syringe 200.Conversely, a smaller angle of the handle 25 relative to the barrel 24results in a shorter distance between the grips 26, 28, limiting thedistance the plunger 23 can be retracted within the barrel 24, therebydecreasing the volume of fluid able to be withdrawn using the syringe200.

In various embodiments, the syringe 200 includes a stopper 20, whichprovides a fixed stopping distance for grips 26, 28. For example, whengrips 26, 28 are squeezed together in the direction of the arrows 29,after they travel a set distance, their movement is stopped by stopper20. In various embodiments, stopper 20 is adjustable. For example,stopper 20 can be configured such that adjusting or rotating stopper 20changes its outer width, thus changing the distance that the grips 26,28 can move during use. This functionality enables adjustment of thevolume of the fluid that can be extracted during use, such as during aparacentesis procedure, (e.g. by applying pressure to the grips 26, 28until the they are stopped by the stopper 20). The stopper 20 eliminatesthe need for direct visualization of the barrel 24 during use, which isoften necessary with conventional devices to determine the volume ofextracted fluid. This also frees users to focus on keeping the syringe200 steady while it is within and proximate sensitive tissue.

In some embodiments, during use of the syringe 200, pressure is placedon the grip 27, and the grips 26, 28 are grasped to stabilize thesyringe 200 while the operator advances the needle 21 into a region ofthe body, for example, the anterior chamber of the eye. Once the needle21 has penetrated the outer layer of the eye (i.e. the cornea), and itstip is within the anterior chamber, pressure is applied to the grips 26and 28 in the direction of the arrows 29 (i.e. the handle 25 iscompressed). As a result, since the plunger 23 and the plunger seal 22are attached to one another and can move freely within the barrel 24,the action of moving the grips 26, 28 in the direction of the arrows 29causes the handle 25 to straighten, withdrawing the plunger 23 and theplunger seal 22 rearwardly, away from the needle 21. In turn, theplunger 23 extends further out of the barrel 24, and the plunger seal 22moves closer to the open end of the barrel 24, generating negativepressure in the barrel 24 to draw out fluid from the anterior chamber ofthe eye into the barrel 24.

FIG. 2B illustrates a cross-sectional view of the syringe 200 of FIG. 2Afrom a horizontal plane extending through the stopper 20, according tovarious embodiments of the present disclosure. In various embodiments,the stopper 20 is a circular dial that surrounds the barrel 24. In someembodiments, the maximum distance the grips 26, 28 can travel can beadjusted by rotating the stopper 20 about the barrel 24. In variousembodiments, the stopper 20 can be rotated to result in multiple optionsfor a maximum travelling distance for the grips 26, 28. For example, thestopper 20 can be rotated to achieve desired elevations 20A, 20B, 20C,20D. Each elevation 20A, 20B, 20C, 20D provides a distinct geometrywhich determines the distance that the grips 26, 28 can travel whensqueezed in the direction of the arrows 29. As a result, the elevationof the stopper 20 can determine how far the plunger 23, and the plungerseal 22 retract in barrel 24, away from the needle 21. This, in turn,determines the volume of fluid extracted during use of syringe 200.

As is depicted in FIG. 2B, the stopper 20 at elevation 20A extends theshortest distance from the barrel 24, enabling the grips 26, 28 to movethe greatest distance in the direction of the arrows 29, and thus,providing a large allowable fluid extraction volume. The stopper 20 atelevation 20B extends a further distance from the barrel 24, limitingthe traveling distance of the grips 26, 28 in the direction of thearrows 29 during the procedure. The stopper 20 at elevation 20C extendseven further from the barrel 24, limiting the available travellingdistance of the grips 26, 28 to a greater degree. The stopper 20 atelevation 20D extends the furthest distance from the barrel 24,providing the most limited travelling distance of the grips 26, 28, andthus, the smallest fluid extraction volume. Various elevations can beprovided in embodiments of the present disclosure, corresponding tovarious allowable extraction volumes. As stated above, the stopper 20 isbeneficial during use of the syringe 200, such as during a paracentesisprocedure, to eliminate user variability and to maximize control of thedevice, without distracting the user during the procedure.

FIG. 3 illustrates a plan view of an embodiment of a syringe 300,according to various embodiments of the present disclosure. The syringe300 includes a needle 31 attached to a barrel 34, and a plunger 33 and aplunger seal 32 disposed, at least in part, within the barrel 34. Thehandle 35 is attached to, or near, the plunger 33 at, or near, terminalendpoints 35A, 35B, and to, or near, the barrel 34 at, or near, terminalendpoints 35D, 35C. In the syringe 300, the terminal endpoints 35D, 35Care disposed at, or near, the open end of the barrel 34. In variousembodiments, attaching the handle 35 at, or near, the open end of thebarrel 34 results in a handle 35 of a smaller size, which may be moreaptly suited for users with smaller hands, or for procedures extractingonly small volumes of fluid.

In various embodiments, the handle 35 is provided in two or morecomponents disposed on different regions of the outer surface of thebarrel 34 and the plunger 33. In some embodiments, the components of thehandle 35 are disposed in diametrical opposition about the barrel 34 andthe plunger 33. The handle 35 may be configured to manipulate theplunger 33, while remaining sufficiently flexible to be compressed inthe direction of the arrows 39. The handle 35 may be provided in avariety of materials, including, but not limited to, various metals,composite materials, and plastics, such as polyethylene, polypropylene,or polyvinyl chloride.

The handle 35 can connect to the plunger 33 and the barrel 34 in avariety of ways. For example, the terminal endpoints 35A, 35B, 35D, 35Cmay comprise connectors that facilitate compression of the handle 35.For example, the terminal endpoints 35A, 35B, 35D, 35C may compriseliving hinges, pin joints, spring hinges, or the like. Alternatively,the handle 35 can be connected to the plunger 33 and the barrel 34 usinga variety of chemical means, including various adhesives, epoxies,welding, or the like. Additionally, in various embodiments, the handle35, the plunger 33, and the barrel 34 may comprise a single,injection-molded component.

In various embodiments, the handle 35 includes grips 36, 38 whichprovide a resting surface for the fingers of the operator of the syringe300. In some embodiments, the grips 36, 38 are diametrically disposedabout the barrel 34, and are provided in a variety of shapes and sizes.For example, the grips 36, 38 may be provided as concave, semi-circularrecesses in the outer surface of the handle 35. In other embodiments,for example, the grips 36, 38 can be provided in similar sizes andshapes, or can be provided in differing sizes and shapes to accommodatevarious possible geometries of an operator's fingers. Additionally, forexample, the grips 36, 38 can include ergonomic contours or siliconepads to reduce pressure points and improve comfort of the syringe 300during use.

In some embodiments, the syringe 300 includes a grip 37 disposed on, orproximate to the plunger 33. The grip 37 provides another restingsurface of at least one finger of an operator, and enables enhancedmanipulation of the device. For example, an operator may place an indexfinger on the grip 37, a thumb on the grip 38, and a middle finger onthe grip 36. An operator may rest their remaining fingers on variousother components or surfaces of the device, including on the handle 35or the barrel 34.

The syringe 300 comprises a needle 31 with a gauge, stiffness, bevel andlength to facilitate penetration of the outer layer of the eye, namelythe cornea, just slightly entering the anterior chamber, minimizing therisk of contacting other intraocular structures.

In some embodiments, during use of the syringe 300, pressure is placedon the grip 37, and the grips 36, 38 are grasped to stabilize the devicewhile the operator advances the needle 31 into the anterior chamber ofthe eye. Once the needle 31 has penetrated the outer layer of the eye(i.e. the cornea), and its tip is within the anterior chamber, pressureis applied on the grips 36 and 38 in the direction of the arrows 39(i.e. the handle 35 is compressed). As a result, since the plunger 33and the plunger seal 32 are attached to one another and can move freelywithin the barrel 34, the action of moving the grips 36, 38 in thedirection of the arrows 39 causes the handle 35 to straighten,withdrawing the plunger 33 and the plunger seal 32 rearwardly, away fromthe needle 31. In turn, the plunger 33 extends further out of the barrel34, and the plunger seal 32 moves closer to the open end of the barrel34, generating negative pressure in the barrel 34 to draw out fluid fromthe anterior chamber of the eye into the barrel 34.

In various embodiments, the syringe 300 can be configured such that themaximum distance that the grips 36 and 38 can travel corresponds to acertain volume of withdrawn fluid. In some embodiments, contact with theouter surface of the barrel 34 prevents the grips 36, 38 fromcompressing further. In other embodiments, some other mechanical limitercan limit the movement of the grips 36, 38, such as stopper 20. Thissafe stop feature of the syringe 300 allows an operator to use thesyringe 300 without an assistant or direct visualization of thewithdrawn liquid.

In some embodiments, the maximum volume of withdrawn fluid is adjustedby changing the angle of the handle 35 relative to the barrel 34. Forexample, increasing the angle of the handle 35 relative to the barrel 34increases the distance between the grips 36, 38, which allows theplunger 33 to be retracted further within the barrel 34, therebyincreasing the volume of fluid able to be withdrawn using syringe 300.Conversely, a smaller angle of the handle 35 relative to the barrel 34results in a shorter distance between the grips 36, 38, limiting thedistance the plunger 33 can be retracted within the barrel 34, therebydecreasing the volume of fluid able to be withdrawn using the discloseddevice

FIG. 4 illustrates a plan view of another embodiment of a syringe 400including handles with different lengths, according to variousembodiments of the present disclosure. In various embodiments, thesyringe 400 includes a needle 41 attached to a barrel 44, and a plunger43 and a plunger seal 42 disposed, at least in part, within the barrel44. The handle 45 is attached to, or near, the plunger 43 at, or near,terminal endpoints 45A, 45B, and to, or near, the barrel 44 at, or near,terminal endpoints 45D, 45C.

In various embodiments, the handle 45 is provided in two or morecomponents disposed on different regions of the outer surface of thebarrel 44 and the plunger 43. In some embodiments, the components of thehandle 45 are disposed in diametrical opposition about the barrel 44 andthe plunger 43. The handle 45 may be configured to manipulate theplunger 43, while remaining sufficiently flexible to be compressed inthe direction of the arrows 49. The handle 45 may be provided in avariety of materials, including, but not limited to, various metals,composite materials, and plastics, such as polyethylene, polypropylene,or polyvinyl chloride.

In various embodiments, the components of the handle 45 each comprise afirst arm of a first length and a second arm of a second length, whereinthe first length is shorter than the second length. In some embodiments,the first and second arms of the handle 45 are flexibly connected bothto each other, to the barrel 44, and to the plunger 43.

The handle 45 can connect to the plunger 43 and the barrel 44 in avariety of ways. For example, the terminal endpoints 45A, 45B, 45D, 45Cmay comprise connectors that facilitate compression of the handle 45.For example, the terminal endpoints 45A, 45B, 45D, 45C may compriseliving hinges, pin joints, spring hinges, or the like. Alternatively,the handle 45 can be connected to the plunger 43 and the barrel 44 usinga variety of chemical means, including various adhesives, epoxies,welding, or the like. Additionally, in various embodiments, the handle45, the plunger 43, and the barrel 44 may be provided as a single,injection-molded component.

In various embodiments, the handle 45 includes grips 46, 47 whichprovide a resting surface for the fingers of the operator of the syringe400. In some embodiments, the grips 46, 47 are diametrically disposedabout the barrel 44, and are provided in a variety of shapes and sizes.For example, the grips 46, 47 may be provided as concave, semi-circularrecesses in the outer surface of the handle 45. In other embodiments,for example, the grips 46, 47 can be the provided in similar sizes andshapes, or can be provided in differing sizes and shapes to accommodatevarious possible geometries of an operator's fingers. Additionally, forexample, the grips 46, 47 can include ergonomic contours or siliconepads to reduce pressure points and improve comfort of the syringe 400during use.

In various embodiments, the syringe 400 comprises a needle 41 with agauge, stiffness, bevel and length to facilitate penetration of theouter layer of the eye, namely the cornea, just slightly entering theanterior chamber, minimizing the risk of contacting other intraocularstructures.

In various embodiments, during use, the syringe 400 is advanced so thatthe needle 41 penetrates the outer layer of the eye, (i.e. the cornea),and enters the anterior chamber of the eye. After the needle 41penetrates the outer layer of the eye, (i.e. the cornea), and its tip ispositioned within the anterior chamber, pressure is applied to the grips46, 47 in the direction of the arrows 49. Applying said pressure movesgrips 46, 47 closer to each other (i.e. compresses the handle 45), andadvances the plunger 43 and the plunger seal 42 forwardly within thebarrel 44, toward the needle 41. The forward movement of the plunger 43and the plunger seal 42 toward the needle 41 generates positive pressurein the barrel 44, and injects fluid from the barrel 44 into the anteriorchamber of the eye.

In some embodiments, contact with the outer surface of the barrel 44prevents further movement of the grips 46, 47 in the direction of thearrows 49. In other embodiments, some other mechanical limiter, forexample the stopper 20, can limit the movement of the grips 46, 47. Thissafe stop feature of the syringe 400 allows an operator to perform aprocedure without an assistant or direct visualization of withdrawnliquid. Another way to predetermine the amount of fluid injected by thesyringe 400 is by adjusting the angle Θ, formed between the handle 45and the barrel 44, i.e., increasing the angle Θ will result in a greaterdistance between the grips 46, 47, and a larger volume of fluid is ableto be ejected from the barrel 44 during use of the syringe 400.

FIG. 5 illustrates an anterior-posterior cross section through theanterior chamber of a human eye. The cornea C is a clear window into theanterior chamber A. The dimensions of the anterior chamber A areapproximately 3 mm deep at the height of the dome of the cornea C, adistance defined as the length from point O to point O′, and 12.5 mmwide, a distance defined as the length from point M to point M′. Theanterior chamber A is the space formed between the posterior edge of thecornea C in the front, and the anterior edge of the lens L and the irisD in the back. The pupil is the opening in the iris D.

Further, the lens L is suspended in the middle of the eye with zonulesF. These zonules are fibers that are anchored at the ciliary body E. Thelimbus is the transition zone between the white part of the eye, thesclera, and the cornea. The limbus is composed of two zones, the 1 mmwhite zone, which is the section of the limbus between the posteriorlimbal border N, and the mid-limbal line Y; and a 1 mm blue zone,between the mid-limbal line Y and the anterior limbal border Z. Thevisual axis V is a zone in the central cornea approximately 3-4 mm wide.While in a conventional anterior chamber paracentesis or intracameralinjection procedure the needle may be inserted only at the limbus, thedevices taught herein allow for safe expansion of the needle insertionzone to include injector zone X, between the anterior limbal border Zand the edge of the visual axis V, and even to include the visual axis Vif deemed medically necessary, e.g., in rare circumstances such assevere peripheral corneal scarring it may be necessary to access theanterior chamber through visual axis V. Axis I shows the direction andangle of penetration into the anterior chamber using the approachestaught herein.

FIG. 6 illustrates an exemplary method describing the anterior chamberparacentesis or intracameral injection procedure using the devicestaught herein. At Step 61, the method in general is described as aprocedure for using an instrument for paracentesis for example syringes100, 200, 300, or 400. In Step 62, the surgical site is prepared, whichincludes anesthetizing and sterilizing the cornea. In Step 63, thepatient is positioned so as to be at a slit lamp or is seated in theexam chair or on a procedure table with their head titled backward. InStep 64, a preferred site to insert the needle of the paracentesisdevice on the corneal surface is selected. In Step 65, the needle isinserted at the selected site on the corneal surface. In Step 66, thehandles, for example the handles 15, 25, 35, or 45 are squeezed (i.e.compressed). In Step 67, the instrument is removed from the eye.Variations of this method will be obvious to a person of ordinary skillin the art, and are encompassed by the present disclosure.

FIG. 7A illustrates a plan view of another embodiment of a syringe 700A,according to various embodiments of the present disclosure. As isdepicted in FIG. 7A, the syringe 700A in this embodiment uses aluer-type syringe 71, which includes a luer connector 72 enablinginterchangeable luer-compatible needles or other luer-compatibledevices, to be attached to the end of the syringe 71. The syringe 700Aalso includes a barrel 74 and a plunger extension 73 coupled to aplunger 76 and a plunger seal (not shown) positioned at least partiallywithin the barrel 74. According to various embodiments, the syringe 700Aincludes first handles 75A, 75B having a first length, and secondhandles 75C, 75D having a second length, wherein the first length islonger than the second length. Handles of different lengths, asillustrated in the syringe 700A of FIG. 7, take advantage of the leverprinciple, which can be advantageous for procedures performed using thepresently-disclosed device.

In some embodiments, the first handles 75A, 75B are flexibly connectedat, or near, the plunger extension 73 at one end, and at, or near, thesecond handles 75C, 75D at another end. In other embodiments, the secondhandles 75C, 75D are flexibly connected at, or near, the first handles75A, 75B at one end, and at or near, the barrel 74 at another end. Thefirst handles 75A, 75B, the second handles 75C, 75D, and theirconnections to one another and/or to other structures may be configuredto enable manipulation of the plunger extension 73, while remainingsufficiently flexible to be compressed in the direction of the arrows79.

The first handles 75A, 75B, and the second handles 75C, 75D can connectto one another, to the plunger extension 73 and the barrel 74 in avariety of ways. For example, the first handles 75A, 75B, and the secondhandles 75C, 75D may include living hinges, pin joints, spring hinges,or the like. Alternatively, the first handles 75A, 75B, and the secondhandles 75C, 75D can connect to one another, to the plunger extension73, and the barrel 74 using a variety of chemical means, includingvarious adhesives, epoxies, welding, or the like. Additionally, invarious embodiments, the first handles 75A, 75B, the second handles 75C,75D, the plunger extension 73, and the barrel 74 may comprise a single,injection-molded component.

In some embodiments, the first handles 75A, 75B, and the second handles75C, 75D are disposed in diametrical opposition about the barrel 74 andthe plunger extension 73. The first handles 75A, 75B, and the secondhandles 75C, 75D may be provided in a variety of materials, including,but not limited to, various metals, composite materials, and plastics,such as polyethylene, polypropylene, or polyvinyl chloride.

In some embodiments, the first handles 75A, 75B are ergonomicallydesigned to provide a comfortable resting surface for the operator'sfingers. Two fingers can be placed on the first handles 75A, 75B. Theremaining fingers of the operator can rest at multiple points along thesyringe 700A. The additional contact points may be used to improvecontrol of the syringe 700A and to stabilize the syringe 700A within thehand of the operator. In some embodiments, a user may position theirremaining fingers on the plunger extension 73 and/or the barrel 74.

In various embodiments, the syringe 700A can be configured such that themaximum distance that the first handles 75A, 75B, and the second handles75C, 75D can be compressed corresponds to a certain volume of withdrawnfluid. In some embodiments, contact with the outer surface of the barrel74 prevents further compression of the first handles 75A, 75B, and thesecond handles 75C, 75D. In other embodiments, some other mechanicallimiter, such as the stopper 20, can limit the distance that the firsthandles 75A, 75B, and the second handles 75C, 75D can be compressed.This safe stop feature of the syringe 700A allows an operator to use thesyringe 700A without an assistant or direct visualization of thewithdrawn liquid.

In some embodiments, the maximum volume of withdrawn fluid is adjustedby changing the angle of the first handles 75A, 75B, and the secondhandles 75C, 75D relative to the barrel 74. For example, increasing theangle of the first handles 75A, 75B, and the second handles 75C, 75Drelative to the barrel 74 increases the distance by which they can becompressed. The larger compression distance allows the plunger 76, andthe plunger seal (not shown) to be retracted further within the barrel74, rearwardly from the luer connector 72, thereby increasing the volumeof fluid able to be withdrawn using syringe 700A. Conversely, a smallerangle of the first handles 75A, 75B, and the second handles 75C, 75Drelative to the barrel 74 results in a shorter distance by which theycan be compressed. This smaller compression distance limits the distancethe plunger 76, and the plunger seal (not shown) can be retracted withinthe barrel 74, rearwardly from the luer connector 72, thereby decreasingthe volume of fluid able to be withdrawn using the syringe 700A.

In some embodiments, pressure is applied on the first handles 75A, 75Bin the direction of the arrows 78. This action can advance the syringe700A and drive a needle through bodily tissue, such as the cornea, intothe anterior chamber of a patient's eye. The design of the first handles75A, 75B, combined with friction forces between the plunger seal (notshown) and the inside wall of the barrel 74, allows a user to apply asufficient pressure on the first handles 75A, 75B to penetrate thecornea, without activating the plunger extension 73.

The maximum force applied on the first handles 75A, 75B before resultingin movement of the plunger extension 73 can allow a user to safelymanipulate and position the syringe 700A device, for example, within theanterior chamber of a human eye. The maximum force applied on the firsthandles 75A, 75B before resulting in movement of the plunger extension73 can be about, more than, or less than 50, 100, 150, 200, 250, 300,350, 400, 420, 440, 460, 480, 500, 520, 540, 560, 580, 600, 650, 700,750 or 800 grams-force (gf). These values can be used to define discreteforces, such as 480 or 500 gf. These values can also be used to define arange of forces, such as from about 460 to 520 gf.

Once the needle has penetrated the outer layer of the eye, (i.e. thecornea), and the needle tip is within the anterior chamber, pressure canthen be applied on the first handles 75A, 75B in the direction of thearrows 79, causing the first handles 75A, 75C, and the second handles75B, 75D to compress and straighten, pulling the plunger extension 73,the plunger 76 and the plunger seal (not shown) rearwardly away from theneedle. The rearward movement of the plunger extension 73, the plunger76, and the plunger seal (not shown) generates negative pressure in thebarrel 74, drawing fluid from the anterior chamber of the eye into thebarrel 74.

In various embodiments, devices of the present disclosure may beprovided in either single-use or reusable configurations. For example,in some embodiments, single-use paracentesis devices may be provided.Additionally, the devices of the present disclosure may be provided inreusable configurations that can be sterilized between uses and mightprovide added value to hospitals or treatment facilities.

FIGS. 7B-7F illustrate other embodiments of the syringe 700A. The otherembodiments are referred to as syringe 700B-700F. To facilitateexplanation, like reference numbers are used in FIGS. 7A-7F.

FIGS. 7A-7C illustrate a syringe 700 as taught herein that includes theplunger extension and different structural arrangements of the handles75A-75D.

FIGS. 7D-7F illustrate a syringe 700 as taught herein without theplunger extension and different structural arrangements of the handles75A-75D.

FIG. 7B illustrates syringe 700B, according to various embodiments ofthe present disclosure having the first handles 75A, 75B, and the secondhandles 75C, 75D of equal length.

FIG. 7C illustrates syringe 700C, according to various embodiments ofthe present disclosure. The syringe 700C includes the first handles 75A,75B having a first length, and the second handles 75C, 75D having asecond length, wherein the first length is shorter than the secondlength.

FIGS. 7A-7C also illustrate different attachment points of the handles75A-75D with respect to the syringe barrel and the plunger.

FIGS. 7D-7F illustrate syringes 700D, 700E, 700F having plunger flanges83, and do not include the plunger extensions as illustrated in FIGS.7A-7C.

FIG. 7D illustrates syringe 700D including the plunger flange 83 and thefirst handles 75A, 75B having a first length, and the second handles75C, 75D having a second length, wherein the first length is longer thanthe second length.

FIG. 7E illustrates syringe 700E including the plunger flange 83 and thefirst handles 75A, 75B having a first length, and the second handles75C, 75D having a second length, wherein the first length is equal tothe second length.

FIG. 7F illustrates syringe 700F including the plunger flange 83 and thefirst handles 75A, 75B having a first length, and the second handles75C, 75D having a second length, wherein the first length is shorterthan the second length.

FIG. 8A illustrates an embodiment of a device including a syringe holdersystem 800, according to various embodiments of the present disclosure.In various embodiments, a conventional syringe 80 can be used with anembodiment of the presently disclosed device. For example, theconventional syringe 80 can be loaded into a syringe holder 86. Invarious embodiments, the syringe holder 86 comprises a syringe barrelcarrier 87, a plunger extension 90, a barrel fixation means 88, aplunger fixation means 89, and handles 81A (not labelled), 81B, 81C, and81D (not labelled). The syringe holder 86 may be configured to securelycontain the conventional syringe 80.

In various embodiments, the conventional syringe 80 comprises a needle81, a barrel 84, barrel flanges 85, a plunger 82, and a plunger flange83 in various configurations. For example, the barrel 84 of theconventional syringe 80 includes the needle 81 at, or near, one endthereof, and the barrel flanges 85 at, or near, another end thereof.Also, the conventional syringe 80 can include the plunger 82 disposed asleast partially within the barrel 84. The plunger 82 can include theplunger flange 83 at, or near, the end of the plunger 82 that is notdisposed within the barrel 84.

In various embodiments, the conventional syringe 80 fits securely withinsyringe holder 86. In some embodiments, the barrel 84 rests within thesyringe barrel carrier 87 such that the barrel flanges 85 align with,and secure into the barrel fixation means 88. In various embodiments,the barrel fixation means 88 includes a channel, or semicircular notchwithin the syringe barrel carrier 87 configured to contain the barrelflange 83 therein.

Additionally, when the barrel 84 rests within the syringe barrel carrier87, the plunger flange 83 will be aligned with, and inserted into theplunger fixation means 89. In various embodiments, the plunger fixationmeans 89 is disposed on, or near, the end of the plunger extension 90most proximate the syringe barrel carrier 87. In some embodiments, theplunger fixation means 89 comprises a hollow, semicircular structureconfigured to receive the plunger flange 83.

For example, the barrel fixation means 88 and the plunger fixation means89 can be provided in a variety of configurations that can accommodatethe plunger flange 83, and the barrel flanges 85, respectively. In someembodiments, for example, the barrel fixation means 88, and the plungerfixation means 89 are sized and shaped such that they achieve apress-fit connection with their respective flanges 85, 83.

Additionally, various mechanical or chemical means may be provided tosecure the conventional syringe 80 to the syringe holder 86. Forexample, various buckles, clasps, ties, straps, adhesives, or the likecan be used to connect the conventional syringe 80 to the syringe holder86. In some embodiments, the syringe holder 86 provides a morecost-effective solution for health care providers to redeem the benefitsof the presently disclosed devices.

In some embodiments, extended the plunger extension 90 provides animproved balance and center of gravity of the syringe holder 86. Invarious embodiments, the handles 81A (not labelled), 81B, 81C, and 81D(not labelled) are provided in a variety of lengths, widths, and surfacegeometries. For example, the handles 81A (not labelled), 81B, 81C, and81D (not labelled) can be the same length, can vary in length, canprovide wide finger rests for increased user comfort, and can includeergonomic contours to reduce pressure points and improve comfort of thesyringe holder 86 during use.

Further, a variety of materials can be used to comprise the syringeholder 86. For example, the syringe holder 86 can comprise at least oneof a metal, plastic, polymer, silicone, or other material or combinationof materials with adequate rigidity/flexibility to successfully injectand aspirate fluid in accordance with the presently disclosed devicesand methods. Further, the syringe holder 86 may comprise multiplecomponents, or may be formed using a mechanical process, such asinjection molding, to provide the syringe holder 86 as a single piece ofmaterial.

In some embodiments, during use of the syringe holder system 800, thesyringe 80 is loaded into the syringe holder 86. In some embodiments, auser positions their fingers on the handles 81A (not labelled), 81B andpositions their remaining fingers on any other surface of the syringeholder system 800. The operator can then advance the tip of the needle81 into some region of the patient, for example, the anterior chamber ofthe eye. Pressure is then applied to the handles 81A (not labelled), 81Bso that they move closer to each other (i.e. the handles 81A (notlabelled), 81B, 81C, 81D (not labelled) are compressed).

As a result, since the handles 81A (not labelled), 81B, 81C, 81D (notlabelled) are coupled to the plunger extension 90 and the plunger seal(not shown), which can move freely within the barrel 84, the action ofcompressing the handles 81A (not labelled), 81B causes the handles 81A(not labelled), 81B, 81C, 81D (not labelled) to straighten, withdrawingthe plunger extension 90, the plunger (not shown), and the plunger seal(not shown) rearwardly, away from the needle 81. In turn, the plunger(not shown), and the plunger seal (not shown) extend further out of thebarrel 84, and the plunger seal (not shown) moves closer to the open endof the barrel 84, generating negative pressure in the barrel 84 to drawout fluid from the anterior chamber of the eye into the barrel 84.

In various embodiments, the syringe holder system 800 can be configuredsuch that the maximum distance that the handles 81A (not labelled), 81B,81C, 81D (not labelled) can be compressed corresponds to a certainvolume of withdrawn fluid. In some embodiments, the handles 81A (notlabelled), 81B, 81C, 81D (not labelled) are prevented from compressingfurther by contact with the outer surface of the barrel 84. In otherembodiments, some other mechanical limiter, such as the stopper 20, canlimit the movement of the handles 81A (not labelled), 81B, 81C, 81D (notlabelled). This safe stop feature of the syringe holder system 800allows an operator to use the syringe holder system 800 without anassistant or direct visualization of the withdrawn liquid.

In some embodiments, the maximum volume of withdrawn fluid is adjustedby changing the angle of the handles 81A (not labelled), 81B, 81C, 81D(not labelled) relative to the barrel 84. For example, increasing saidangle increases the distance the handles 81A (not labelled), 81B, 81C,81D (not labelled) can be compressed, which allows the plunger (notshown) to be retracted further within the barrel 84, thereby increasingthe volume of fluid able to be withdrawn using the syringe holder system800. Conversely, a smaller angle of the handles 81A (not labelled), 81B,81C, 81D (not labelled) relative to the barrel 84 results in a shorterdistance that the handles 81A (not labelled), 81B, 81C, 81D (notlabelled) can be compressed, limiting the distance the plunger (notshown) can be retracted within the barrel 84, thereby decreasing thevolume of fluid able to be withdrawn using the syringe holder system800.

FIG. 8B illustrates another embodiment of a device including a syringeholder system 800, according to various embodiments of the presentdisclosure. In various embodiments, a conventional syringe 80′ can beused with an embodiment of the presently disclosed device. For example,the conventional syringe 80′ can be loaded into a syringe holder 86′. Invarious embodiments, the syringe holder 86′ comprises a syringe barrelcarrier 87′, a barrel fixation means 88′, a plunger fixation means 89′,and handles 81A′ (not labelled), 81B′, 81C′, and 81D′ (not labelled).The syringe holder 86′ may be configured to securely contain theconventional syringe 80.

In various embodiments, the conventional syringe 80′ comprises a needle81′, a barrel 84′, barrel flanges 85′, a plunger 82′, and a plungerflange 83′ in various configurations. For example, the barrel 84′ of theconventional syringe 80′ includes the needle 81′ at, or near, one endthereof, and the barrel flanges 85′ at, or near, another end thereof.Also, the conventional syringe 80′ can include the plunger 82′ disposedas least partially within the barrel 84′. The plunger 82′ can includethe plunger flange 83′ at, or near, the end of the plunger 82′ that isnot disposed within the barrel 84′.

In various embodiments, the conventional syringe 80′ fits securelywithin syringe holder 86′. In some embodiments, the barrel 84′ restswithin the syringe barrel carrier 87′ such that the barrel flanges 85′align with, and secure into the barrel fixation means 88′. In variousembodiments, the barrel fixation means 88′ includes a channel, orsemicircular notch within the syringe barrel carrier 87′ configured tocontain the barrel flange 83′ therein.

Additionally, when the barrel 84′ rests within the syringe barrelcarrier 87, the plunger flange 83 will be aligned with, and insertedinto the plunger fixation means 89. In various embodiments, the plungerfixation means 89 is disposed on, or near, and one end of the handles81A′ (not labelled), 81B′. In some embodiments, the plunger fixationmeans 89′ comprises a hollow, semicircular structure configured toreceive the plunger flange 83′.

For example, the barrel fixation means 88′ and the plunger fixationmeans 89′ can be provided in a variety of configurations that canaccommodate the plunger flange 83′, and the barrel flanges 85′,respectively. In some embodiments, for example, the barrel fixationmeans 88′, and the plunger fixation means 89′ are sized and shaped suchthat they achieve a press-fit connection with their respective flanges85′, 83′.

Additionally, various mechanical or chemical means may be provided tosecure the conventional syringe 80′ to the syringe holder 86′. Forexample, various buckles, clasps, ties, straps, adhesives, or the likecan be used to connect the conventional syringe 80′ to the syringeholder 86′. In some embodiments, the syringe holder 86′ provides a morecost-effective solution for health care providers to redeem the benefitsof the presently disclosed devices.

In various embodiments, the handles 81A′ (not labelled), 81B′, 81C′, and81D′ (not labelled) are provided in a variety of lengths, widths, andsurface geometries. For example, the handles 81A′ (not labelled), 81B′,81C′, and 81D′ (not labelled) can be the same length, can vary inlength, can provide wide finger rests for increased user comfort, andcan include ergonomic contours to reduce pressure points and improvecomfort of the syringe holder system 800 during use.

Further, a variety of materials can be used to comprise the syringeholder 86′. For example, the syringe holder 86′ can comprise at leastone of a metal, plastic, polymer, silicone, or other material orcombination of materials with adequate rigidity/flexibility tosuccessfully inject and aspirate fluid in accordance with the presentlydisclosed devices and methods. Further, the syringe holder 86′ maycomprise multiple components, or may be formed using a mechanicalprocess, such as injection molding, to provide the syringe holder 86′ asa single piece of material.

In some embodiments, during use of the syringe holder system 800′, theconventional syringe 80′ is loaded into the syringe holder 86′. In someembodiments, a user positions their fingers on the handles 81A′ (notlabelled), 81B′ and positions their remaining fingers on any othersurface of the syringe holder system 800′. The operator can then advancethe tip of the needle 81′ into some region of the patient, for example,the anterior chamber of the eye. Pressure is then applied to the handles81A′ (not labelled), 81B′ so that they move closer to each other (i.e.the handles 81A (not labelled), 81B, 81C, 81D (not labelled) arecompressed).

As a result, since the plunger 82′ is attached to the handles 81A′ (notshown), 81B′, via the plunger fixation means 89′, the action ofcompressing the handles 81A (not labelled), 81B causes the handles 81A(not labelled), 81B, 81C, 81D (not labelled) to straighten, withdrawingthe plunger (not shown), and the plunger seal (not shown) rearwardly,away from the needle 81′. In turn, the plunger (not shown), and theplunger seal (not shown) extend further out of the barrel 84′, and theplunger seal (not shown) moves closer to the open end of the barrel 84′,generating negative pressure in the barrel 84′ to draw out fluid fromthe anterior chamber of the eye into the barrel 84′.

In various embodiments, the syringe holder system 800′ can be configuredsuch that the maximum distance that the handles 81A′ (not labelled),81B′, 81C′, 81D′ (not labelled) can be compressed corresponds to acertain volume of withdrawn fluid. In some embodiments, the handles 81A′(not labelled), 81B′, 81C′, 81D′ (not labelled) are prevented fromcompressing further by contact with the outer surface of the barrel 84′.In other embodiments, some other mechanical limiter, such as the stopper20, can limit the compression of the handles 81A′ (not labelled), 81B′,81C′, 81D′ (not labelled). This safe stop feature of the syringe holdersystem 800′ allows an operator to use the syringe holder system 800′without an assistant or direct visualization of the withdrawn liquid.

In some embodiments, the maximum volume of withdrawn fluid is adjustedby changing the angle of the handles 81A′ (not labelled), 81B′, 81C′,81D′ (not labelled) relative to the barrel 84′. For example, increasingsaid angle increases the distance the handles 81A′ (not labelled), 81B′,81C′, 81D′ (not labelled) can be compressed, allows the plunger (notshown) to be retracted further within the barrel 84′, thereby increasingthe volume of fluid able to be withdrawn using the syringe holder system800′. Conversely, a smaller angle of the handles 81A′ (not labelled),81B′, 81C′, 81D′ (not labelled) relative to the barrel 84′ results in ashorter distance that the handles 81A′ (not labelled), 81B′, 81C′, 81D′(not labelled) can be compressed, limiting the distance the plunger (notshown) can be retracted within the barrel 84′, thereby decreasing thevolume of fluid able to be withdrawn using the syringe holder system800′.

The embodiments of the disclosed paracentesis device provide a number ofadvantages over current devices and methods. A differentiating featureof the presently disclosed device is that it is ergonomically designedfor optimal grip, contact area, and manipulation. Further, the presentlydisclosed device may comprise a barrel including gradation marks toprecisely indicate even small volumes of fluid. Additionally, thepresently disclosed devices provide for the aspiration of apredetermined amount of fluid using variety of means, including, but notlimited to mechanical devices, such as stopper 20.

Additionally, the devices of the present disclosure can allow for acontrolled rate of aspiration. A controlled aspiration rate can reducepotential damage to surrounding tissue during the paracentesisprocedure. A further differentiating feature of the presently discloseddevice is that the inner lining of the syringe barrel may be coated withmaterials beneficial for storing a particular fluid. A yet furtherdifferentiating feature of the presently disclosed device is that, insome embodiments, it does not require a separate aspirating device tocreate negative pressure or suction.

While this design in any of its embodiments can be used in aconventional paracentesis procedure of the anterior chamber, a yetfurther differentiating feature is that, in any of its embodiments, theneedle length provides the surgeon with more flexibility in selectingthe safest possible location on the cornea to access the chamber in agiven patient. Thus, the paracentesis or injection devices of theembodiments taught herein are safer and easier to control thanconventional apparatuses.

The foregoing description of example embodiments of the inventionprovides illustration and description, but is not intended to beexhaustive or to limit the invention to the precise form disclosed.Modifications and variations are possible in light of the aboveteachings or may be acquired from practice of the invention. Forexample, while a series of acts has been described, the order of theacts may be modified in other implementations consistent with theprinciples of the invention. Further, non-dependent acts may beperformed in parallel.

It should be appreciated that the various embodiments individuallydescribed herein may be practiced in combination in certaincircumstances without departing from the scope of the present invention.Other embodiments will be apparent to those skilled in the art fromconsideration of the specification and practice of this disclosure. Itis intended that the specification and examples be considered asexemplary only, with the true scope and spirit of the disclosed devicesand methods being indicated by the claims.

What is claimed is:
 1. A syringe comprising: a syringe barrel having afirst end couplable to a needle and an open second end; a plunger sealdisposed inside the syringe barrel; a plunger rod disposed in thesyringe barrel extending along a longitudinal axis between a first endcoupled to the plunger seal and a second end opposite of the first end;and at least one compressible handle coupled between a portion of thesyringe barrel and the second end of the plunger rod, whereincompressing the handle causes the syringe plunger to move rearwardly inthe syringe barrel away from the needle.
 2. The syringe of claim 1,wherein the syringe is an aspirating syringe.
 3. A syringe comprising: asyringe barrel having a first end couplable to a needle and an opensecond end; a plunger seal disposed inside the syringe barrel; a plungerrod disposed in the syringe barrel extending along a longitudinal axisbetween a first end coupled to the plunger seal and a second endopposite of the first end; and at least one handle coupled between aportion of the syringe barrel and the second end of the plunger rod,wherein compressing the handle causes the syringe plunger to moveforwardly in the syringe barrel toward the needle.
 4. A method foraspirating a fluid comprising: inserting a needle of a syringe deviceinto a chamber such that the needle is in fluid communication with bothan interior of the chamber and a syringe barrel of the syringe, thesyringe including a plunger seal disposed inside the syringe barrel, aplunger rod disposed in the syringe barrel extending along alongitudinal axis between a first end coupled to the plunger seal and asecond end opposite of the first end, and a compressible handle coupledbetween a portion of the syringe barrel and the second end of theplunger rod; and compressing the compressible handle to move the plungerrod and the plunger seal rearwardly within the syringe barrel away fromthe needle to draw fluid from the chamber into the syringe barrel.
 5. Amethod for injecting a fluid comprising: inserting a needle of a syringedevice into an injection site, the syringe including a plunger sealdisposed inside a syringe barrel, a plunger rod disposed in the syringebarrel extending along a longitudinal axis between a first end coupledto the plunger seal and a second end opposite of the first end, and acompressible handle coupled between a portion of the syringe barrel andthe second end of the plunger rod; and compressing the compressiblehandle to move the plunger rod and the plunger seal forwardly within thesyringe barrel toward the needle to inject a fluid from the syringebarrel into the injection site.